fs: annotate ->poll() instances

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 21e6fee..67fb3b8 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -920,7 +920,7 @@
 	return 0;
 }
 
-static unsigned int ep_eventpoll_poll(struct file *file, poll_table *wait)
+static __poll_t ep_eventpoll_poll(struct file *file, poll_table *wait)
 {
 	struct eventpoll *ep = file->private_data;
 	int depth = 0;